Add in the timezone global from time.h, from a patch by

Jon Nelson <jnelson@boa.org>

libc/misc/time/tm_conv.c

@@ -81,6 +81,9 @@ static const unsigned short int __mon_lengths[2][12] = {
 	/* Leap years.  */
 	{31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
 };
+/* This global is exported to the wide world in keeping
+ * with the interface in time.h */
+long int timezone;
 
 
 void __tm_conv(tmbuf, t, offset)
@@ -92,6 +95,8 @@ time_t offset;
 	register int y;
 	register const unsigned short int *ip;
 
+	timezone = offset;
+
 	days = *t / SECS_PER_DAY;
 	rem = *t % SECS_PER_DAY;
 	rem += offset;